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A noninvasive handheld assistive device to accommodate essential tremor: A pilot study


  • Funding agencies: This study was supported by NIH grant 5R44NS070438.

  • Relevant conflicts of interest/financial disclosures: Anupam Pathak is the CEO and founder of Lift Labs Design (his company is commercializing ACT technology for this device that will be released in 2013 and is funded by NIH grant 5R44NS070438) and is an inventor on two patents for Active Cancellation of Tremor Technology. John A.Redmond is a consultant for Lift Labs Design. Michael Allen is an employee of Lift Labs Design.

  • Full financial disclosures and author roles may be found in the online version of this article.



We explored whether a noninvasive handheld device using Active Cancellation of Tremor (ACT) technology could stabilize tremor-induced motion of a spoon in individuals with essential tremor (ET).


Fifteen ET subjects (9 men, 6 women) performed 3 tasks with the ACT device turned on and off. Tremor severity was rated with the Fahn-Tolosa-Marin Tremor Rating Scale (TRS). Subjective improvement was rated by subjects with the Clinical Global Impression Scale (CGI-S). Tremor amplitude was measured using device-embedded accelerometers in 11 subjects.


TRS scores improved with ACT on (versus off) in all 3 tasks: holding (1.00 ± 0.76 vs. 0.27 ± 0.70; P = 0.016), eating (1.47 ± 1.06 vs. 0.13 ± 0.64; P = 0.001), and transferring (1.33 ± 0.82 vs. 0.27 ± 0.59; P = 0.001). CGI-S improved with eating and transferring, but not the holding task. Accelerometer measurements demonstrated 71% to 76% reduction in tremor with the ACT device on.


This noninvasive handheld ACT device can reduce tremor amplitude and severity for eating and transferring tasks in individuals with ET. © 2013 International Parkinson and Movement Disorder Society